Tractor loaders or front-end loaders such as described in U.S. Pat. No. 4,051,962 include a frame means which is mounted on the tractor and which has a pair of boom arms pivotally mounted on towers on the frame means. Hydraulic cylinders are operatively connected to and extend between the frame means and the boom arms for raising and lowering the boom arms relative to the frame means and the tractor. Some form of materials handling attachment such as a hay spike, grapple hook, bucket, etc. is normally pivotally mounted on the forward ends of the boom arms and are pivoted with respect thereto by a pair of hydraulic cylinders. The vertical height to which the attachment may be raised is limited by the length of the boom arms, the hydraulic cylinders connected thereto which raise and lower the boom arms, and the height of the towers. The height limitation of the conventional front-end loaders sometimes prevents the loader from being used to stack hay bales or the like.
The height limitation of the conventional front-end loaders may be easily overcome by simply lengthening the boom arms but the increase in the length of the boom arms seriously detracts from the compactness and maneuverability of the tractor loader since greater boom arms length is not always required and it is sometimes desirable to have a tractor loader which has relatively short arms and/or a low profile.
It is therefore a principal object of the invention to provide an improved tractor loader.
A further object of the invention is to provide an improved tractor loader having an extension arm assembly removably mounted thereon which enables the materials handling attachment thereon to be raised to a greater height than that possible with the conventional loader.
Yet another object of the invention is to provide an improved tractor loader having an extension arm assembly which is quickly and easily mounted on the ends of the boom arms without modification thereof.
Still another object of the invention is to provide a tractor loader having an extension arm assembly which enables a materials handling attachment such as a bucket to be "rolled" back.
Still another object of the invention is to provide a tractor loader of the type described which is economical of manufacture, durable in use and refined in appearance. These and other objects will be apparent to those skilled in the art.